Darvish (9-5) scattered five hits and struck out 12 over 6 2/3 innings and former Blue Jay Arencibia hit a three-run homer to help the Texas Rangers end their eight-game losing streak with a 5-1 win over Toronto on Friday night.
Dickey (7-10) started strongly for the Jays but paid for a seventh-inning knuckleball that got away and was slammed into the left-field seats by Arencibia.
"It just knuckled into the barrel, thankfully, because the other ones I swung and missed by a foot," said Arencibia, who struck out twice.
Dickey has now lost six of his last seven starts, during which the Jays have scored a total of 11 runs.
It was a matchup of two teams in a nosedive, played before 38,012 on a pleasant 22-degree night with the roof open at Rogers Centre.
The Rangers (39-57), mired in the longest current losing streak in the majors, had lost 14 of their last 15 games and 22 of 25. Toronto (49-48) had dropped eight of its last 10, 11 of 15 and 17 of 25.
But Darvish proved to be the tonic needed for Texas, which is now 12-6 this season when the elegant right-hander from Japan starts. Through six innings, every Blue Jays starter had struck out at least once and Texas finished with 17 strikeouts on the night.
"It started on the mound," said Texas manager Ron Washington. "Yu was able to pitch around some traffic that he had on the bases and make some pitches in some key situations. He kept us in the ball game until we could get something going offensively.
Despite a slump of its own, Toronto came into the game second in the AL East, four games back of Baltimore, while Texas was last in the AL West, 21 games behind the leading Athletics.
Texas has a league-leading 15 players on the disabled list. The Rangers also lead the majors in players (50) and pitchers (30) used in 2014, and, with 15 rookies, is tied with Arizona for another MLB first.
Like the Rangers, Toronto is missing key personnel. But manager John Gibbons wasn't making excuses.
"When guys like Darvish are on, I don't care what your lineup looks like. They're going to cut you up pretty good. They're going to limit your opportunities," he said. "We had a couple tonight that we didn't cash in. We left a few guys on base (nine). That's why he's one of the top pitchers in baseball. But I mean we've been in an offensive drought for a while now. And we're due to break something out."
It marked the sixth time this season that Darvish, who tied his season high for Ks, has recorded double-digit strikeouts.
Toronto, which has now lost three straight games, had won eight of its last 10 against Texas since the start of 2013. The Jays offence continued to sputter, with one run on seven hits.
Dickey opened strongly before faltering in the fifth when Adrian Beltre ended the knuckleballer's scoreless run with a leadoff homer. Dickey had faced the minimum 12 batters in the first four innings before giving up the line-drive shot over the right-field fence on a 3-1 delivery, Beltre's 14th homer of the season.
Two outs later, Dickey hit Arencibia with a knuckleball that got away and second baseman Rougned Odor tripled him home to increase the lead to 2-0.
Arencibia, a catcher making his MLB debut at first base, made it 5-0 with one out in the seventh when he cashed in back-to-back singles with his homer.
"A big blow," said Gibbons.
"I hope it gives him confidence," Washington said of Arencibia. "He certainly didn't lack it when he arrived here from the minor leagues. It was nice for him to come through right there. It was big, it was huge. Getting hit by the pitch was huge, too. He had a good night back. It's got to continue. At least he gives us some threat in that lineup."
Colby Rasmus pulled one back with a leadoff homer to right field in the seventh, his 13th of the season. Darvish exited two outs later with the Jays having men on second and third after a walk and single. Left-hander Neal Cotts induced Melky Cabrera to fly out to end the inning.
The Rasmus home run ended a scoreless streak of 16 innings — and a 42-inning run without a homer for the Jays, who lead the majors in home runs.
Darvish walked three and had two wild pitches, throwing 117 pitches including 69 strikes.
Dickey gave up five earned runs on six hits in seven innings, striking out seven while walking two. He threw 109 pitches, 75 for strikes.
"I thought Dickey was good. The three-run homer, of course, hurt," said Gibbons. "But he's been on a nice roll pitching. We're not winning his games. We're not scoring runs in his games. But take away that home run, I thought he was really good."
The combined salaries of Dickey (US$12 million) and Darvish ($10 million) would nearly cover half of the CFL's salary cap hit. And they wasted little time showing why they collected such hefty paycheques.
Dickey retired the first seven batters he faced before giving up a single to Odor. A pretty double play by Munenori Kawasaki ended the inning quickly, however.
Darvish also kept the Jays off the bases in the early going with just two walks and two singles in the first five innings. Toronto had men on first and second with one out in the second but Darvish snuffed out the threat with two straight strikeouts. He struck out two more to end the fifth after walking Juan Francisco.
Darvish did it again in the sixth, striking out two after Cabrera led off the inning with a bloop single before stealing second.
Darvish had not pitched since July 9 other than an inning in Tuesday's all-star game. The six-foot-five right-hander came into the game having given up at least four earned runs in four of his last five starts.
The game marked back-to-back starts for Dickey, who was on the mound for Toronto's last game before the all-star break — allowing two runs in six innings in a 3-0 loss to Tampa.
He said the lack of run support was not in his mind.
"No, not really. I can't control any of that. I have a hard enough time tending to my own garden. If I can just concentrate on being me and hopefully I'll get us deep into the ball game with a chance to win the game, hopefully I haven't given up any runs. That's all I can do. And that's all I try to do."
Aaron Loup, Todd Redmond and Dustin McGowan followed Dickey. Closer Joakim Soria pitched the ninth for Texas, striking out two and giving up a single.
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